This description relates to signal processing that exploits masking behavior of the human auditory system to reduce perception of undesired signal interference, and to a system for producing acoustically isolated zones to reduce noise and signal interference.
Ever since audible signals haves been broadcast and reproduced from recordings, a wide variety of content has been provided for selection by listeners. For example, passengers traveling in a vehicle may each have a different favorite radio station or recording (e.g., compact disc, etc.). However, only a single station may be selected at a time for broadcast from the vehicle's radio. Similarly, different passengers may want to listen to different types and genres of recorded material (e.g., music from a compact disc or memory device) with vehicle audio equipment (e.g., compact disc player). However, only a single selection (e.g., compact disc track) at a time may be played back. In addition, the perception of the played back selection may be degraded due to interference from sources of noise both internal and external to the vehicle. For example, along with engine noise and passenger voices, as the vehicle travels through a noisy environment (e.g., a urban center), relatively loud noises may drown out a selected radio station or recording playback and produce a disagreeable listening experience for the passengers.